How Clinton’s 3 debate performances left the Trump campaign in ruins

Democratic U.S. presidential nominee Hillary Clinton reacts near Republican U.S. presidential nominee Donald Trump after their third and final 2016 presidential campaign debate at UNLV in Las Vegas, Nevada, U.S., October 19, 2016.

The third and final presidential debate has ended, and it can now be said: Hillary Clinton crushed Donald Trump in the most effective series of debate performances in modern political history.

The polling tells the story. As Nate Silver notes, on the eve of the first presidential debate, Clinton led by 1.5 points. Before the second, she was up by 5.6 points. Before the third, she was winning by 7.1 points. And now, writing after the third debate — a debate in which Trump said he would keep the nation "in suspense" about whether there would be a peaceful transition of power, bragged about not apologizing to his wife, and called Clinton "such a nasty woman" — it's clear that Trump did himself no favors. Early polls also suggest Clinton won.

And it's not just the presidential race. Betting markets now predict Democrats will win the Senate. Polls have started showing Democrats in striking distance of the House. The GOP has collapsed into a mid-election civil war, with the party's presidential nominee openly battling the speaker of the House.

This is not normal. As Andrew Prokop concluded in his review of the political science evidence around presidential debates, "There's little historical evidence that they've ever swung polls by more than a few percentage points." In this case, they did. And it's because Clinton executed a risky strategy flawlessly.

The dominant narrative of this election goes something like this. Hillary Clinton is a weak candidate who is winning because she is facing a yet weaker candidate. Her unfavorables are high, her vulnerabilities are obvious, and if she were running against a Marco Rubio or a Paul Ryan, she would be getting crushed. Lucky for her, she's running against a hot orange mess with higher unfavorables, clearer vulnerabilities, and a tape where he brags about grabbing women "by the pussy."

There's truth to this narrative, but it also reflects our tendency to underestimate Clinton's political effectiveness. Trump's meltdown wasn't an accident. The Clinton campaign coolly analyzed his weaknesses and then sprung trap after trap to take advantage of them.

Clinton's successful execution of this strategy has been, fittingly, the product of traits that she's often criticized for: her caution, her overpreparation, her blandness. And her particular ability to goad Trump and blunt the effectiveness of his political style has been inextricable from her gender. The result has been a political achievement of awesome dimensions, but one that Clinton gets scarce credit for because it looks like something Trump is doing, rather than something she is doing — which is, of course, the point.

It began in the first debate. "Donald," she kept saying. No one quite knows why Trump so loathes the sound of his first name, but he does. He quickly tried to shame Clinton into showing him more respect. "Secretary Clinton -- yes, is that okay?" he said, after she once again called him Donald. "Good. I want you to be very happy. It's very important to me."

Clinton's next answer: "In fact, Donald was one of the people who rooted for the housing crisis..."

Each debate has followed the same pattern. Trump begins calm, but as Clinton needles him, he falls apart, gets angrier, launches bizarre personal attacks, offers rambling justifications for his own behavior, and loses the thread of whatever question was actually asked of him.

Clinton, meanwhile, crisply summarizes the binders full of policy information she absorbed before the debate. The gap in preparation, knowledge, and basic competence has been evident in every contest, and it's led to polls showing that even voters who loathe Clinton recognize she's far more qualified and capable than Trump. Nor does Clinton make mistakes — she's often criticized for being careful and bland in her answers, but here it's helped her, as she's never taken the headlines away from Trump's own gaffes.

But Trump's true meltdown was triggered in a specific moment at the end of the first debate.

HOLT: We are at — we are at the final question.

CLINTON: Well, one thing. One thing, Lester.

HOLT: Very quickly, because we're at the final question now.

CLINTON: You know, he tried to switch from looks to stamina. But this is a man who has called women pigs, slobs, and dogs, and someone who has said pregnancy is an inconvenience to employers, who has said…

TRUMP: I never said that.

CLINTON: …women don't deserve equal pay unless they do as good a job as men.

TRUMP: I didn't say that.

CLINTON: And one of the worst things he said was about a woman in a beauty contest. He loves beauty contests, supporting them and hanging around them. And he called this woman "Miss Piggy." Then he called her "Miss Housekeeping," because she was Latina. Donald, she has a name.

TRUMP: Where did you find this? Where did you find this?

CLINTON: Her name is Alicia Machado.

TRUMP: Where did you find this?

CLINTON: And she has become a US citizen, and you can bet…

TRUMP: Oh, really?

CLINTON: …she's going to vote this November.

This was the beginning of Trump's collapse. He would spend the next few days litigating and relitigating his humiliation of Machado. He took to Twitter in the middle of the night to tell Americans to watch a sex tape of Machado that didn't exist.

The moment set in motion all that came next. It set off the explosive debate about the language Trump uses to talk about women. It was the context for the leaked audio of Trump from 2005. It's what led Trump to go full Breitbart and try to turn the second debate into a referendum on Bill Clinton's sexual past — a strategy that top Republicans had warned him against, and that widened the gap between the GOP and its presidential nominee.

Clinton was able to make Trump's treatment of women the issue in part because she and her campaign had prepared to make Trump's treatment of women the issue, and in part because she is a woman and her assault on Trump flummoxed his usual mode of defense, which is to dominate and insult the other men on the stage. By the end of the final debate, Trump was reduce to spitting that Clinton was "such a nasty woman," a line that spoke to both his horror at being challenged by a woman and his complete inability to control what came out of his mouth after 80 minutes on a stage with Clinton.

Two things have been true throughout the debates. One is that Trump has been, at every turn, underprepared, undisciplined, and operating completely without a strategy. In one of the third debate's most unintentionally revealing moments, Trump said, "I sat in my apartment today ... watching ad after false ad, all paid for by your friends on Wall Street," an inadvertent admission that he was inhaling cable news when he should have been prepping for the debate.

But the other reality is that Clinton has been, at every turn, prepared, disciplined, and coldly strategic. She triggered Trump's epic meltdown purposely, and kept Trump off balance over multiple weeks that probably represented his last chance to turn the election around. She was ready for every question, prepared for every attack, and managed to goad Trump into making mistakes that became the main story the day after every single debate.

It is easy, now, to assume her victory was assured, to read Trump's collapse as inevitable. But remember that he triumphed over a talented, 17-person Republican field in debate after debate to win the primary — one-on-one contests are unique, it's true, but there was no particular reason to think Trump couldn't use his bullying, blustering showmanship to take over the stage and expose Clinton as inauthentic and out of touch. The reason he didn't is because she never let him.

We aren't used to this kind of victory. We aren't used to candidates winning not so much because of how they performed but because of how they pushed their opponent into performing. But the fact that we aren't used to this kind of victory doesn't make it any less impressive. Hillary Clinton has humbled Donald Trump, and she did it her way.

Commentary by Ezra Klein, the editor-in-chief of Vox. Follow him on Twitter @ezraklein.

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